Nowadays, since the need for information is increasing, for accordance with ever-increasing demands for higher operating speeds, versatility, integration and lightweight miniaturization etc. of electronic devices, the process technology also tends to develop semiconductor with miniaturization and high density. In order to reduce the packaging volume, as well as to increase the function of the packaging devices, several advanced packaging technologies, for example, flip-chip package, ball-grid array (BGA) package and chip-scale package (CSP) etc., are widely applied in the industry. As the substrate type carrier has advantages of fine wirings, compact package and well performance etc., it is widely applied in the aforementioned advanced package technology.
Reference is made to FIG. 1, which depicts a top view of a prior substrate strip. The substrate strip 100 is, for example, a multilayer board, which comprises a plurality of substrate units 110 and a frame 120 surrounding the substrate units 110. Each substrate unit 110 is defined as a packaging area, which is assembled with a chip (not shown) together during a packaging process, so as to form a packaging structure (not shown). Comparatively, the frame 120 is defined as a non-packaging area. A plurality of slits 130, which are formed between the substrate unit 110 and the frame 120, separate the substrate 110 from the frame 120, so that the substrate unit 110 is partially connected to the frame 120. After completing the packaging process, a separating process may be performed for separating the substrate 110 from the frame 120, so as to form a plurality of separate packaging structures (not shown). Typically, the frame 120 of the packaging substrate 100 has an identification mark 140 disposed thereon, for identifying the lot number and related process information of the packaging substrate strip 100. Consequently, when there are some qualitative problems occurred in the packaging substrate strip 100, the identification mark 140 can be available to trace the lot number and all related process information of the packaging substrate strip 100, so as to clarify the reason why the problems occurred and to provide trouble shooting. However, once the packaging substrate strip 100 is assembled with the chip together and the packaging process is completed, the separating process will be completed to separate the substrate unit 110 from the frame 120. At this time, if there are some qualitative problems occurring in the separate packaging structures, it will be very difficult to find out which lot number of the packaging substrate strip 100 is used in the separate packaging structures. This results in more difficulties in monitoring process and trouble shooting, as well as less product yield.